Motor vehicles powered by an internal combustion engine typically include a liquid cooling system that maintains the engine at an operating temperature. The cooling system typically includes a liquid coolant, a heat exchanger, and an airflow assembly. A pump circulates the coolant through the engine and the heat exchanger, which is typically referred to as a radiator. The coolant extracts heat energy from the engine. As the coolant flows through the radiator, the heat energy extracted by the coolant is dissipated to atmosphere, thereby preparing the coolant to extract additional heat energy from the engine. To assist in dissipating the heat energy of the coolant, the radiator typically includes numerous fins that define many channels. As the vehicle is driven, ambient temperature air from atmosphere is directed through the channels to dissipate the heat energy.
The airflow assembly includes a shroud and a fan assembly. Typically, the shroud is positioned to cause the ambient temperature air from atmosphere to flow through the channels defined by the radiator, instead of blowing around the sides of the radiator. The fan assembly is typically connected to the shroud. When the fan assembly is operated it assists in moving air through the channels of the radiator, even when the vehicle is stationary. Operation of the fan assembly, however, typically causes the airflow assembly to generate some noise that may be objectionable to some users.
Accordingly, it is desirable to improve the airflow assembly so that the noise generated by the airflow assembly is unobjectionable to most users.